Mechanical Properties and Microstructure of Slag Solidified Body

Abstract

The mechanical properties of slag solidified bodies tend to be degraded when the temperature of slag solidified bodies is high. It is easy to crack under the action of perforated fracturing to lose the effect of sealing and interlayer sealing, and affect the cementing quality. Therefore, the mechanical properties of the solidified slag at several bottom-hole cyclic temperatures (30 °C, 50 °C, 70 °C, 90 °C) were studied in the present investigation. The results showed that the early strength of the slag solidified body cured at 90 °C was stronger than the early strength of the slag solidified body at 30 °C and 50 °C but lower than 70 °C. However, when the curing time reaches 28 days, the compressive strength of the slag solidified body at 90 °C droped sharply lower than the strength of the slag solidified body at 30°C. SEM and XRD indicated that the hydration products of slag at 90 °C were primarily network-like C-S-H gels. Compared with low temperature conditions, slag solidified bodies at high temperatures (>90 °C) were prone to micro-cracks and the structure easily damaged.